Health ConsultationsLisa Quiggle, MPHMichigan Department of Health and Human Services
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Completed Exposure Pathway
Source of contaminants
A pathway to move contaminants in the environment
(groundwater, air)
A place where people contact the
contamination
Route of exposure (inhalation, touching)
People have to be present
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First Step:Identify Exposure Pathways
Inhalation
Drinking
Direct Contact
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Next Step is to gather data
Past – no data on historical groundwater or indoor air concentrations
Current – data on groundwater and indoor air
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Exposure Pathway Analysis
Source Environmental Medium Exposure Point Exposure Route Exposed
Population Time Frame Exposure
Solvents from Livonia
Transmission Plant
Groundwater Indoor air Inhalation ResidentsPast Unknown
PresentPotential
Future
Soil gas Indoor air Inhalation ResidentsPast Unknown
PresentPotential
Future
Groundwater Groundwater in yards
Incidental ingestion and
dermal contact Residents
Past UnknownPresent
PotentialFuture
Groundwater Drinking water Ingestion ResidentsPast
IncompletePresentFuture
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Review the scientific literature
Identify key studies
Translate information into screening levels
for humans, using reasonable
worst-case assumptions
Use screening levels to evaluate
exposures
Update screening levels as new science
emerges
How are screening levels developed and used?
Next:Use Screening Levels to Evaluate Potential Exposures
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Health interpretation of indoor air screening levels
• Exposure at or below the screening level
• No significant increased risk of health effects for sensitive individuals who have been exposed under reasonable worst-case conditions
• Exposure above the screening level• Indicates that contamination poses a
health hazard• Does not indicate that health effects will
necessarily occur
• Development of health effects depends on personal factors
• Level and duration of exposure• Individual sensitivity• Genetics• Existing health conditions• Lifestyle factors• Exposure from other sources
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Health Consultation Timeline
Continue to collect data
Evaluate exposure data
Document conclusions in report
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Chemicals and health effects
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Health effects from low-level exposure• We will focus on health effects that are relevant to typical vapor
intrusion scenarios• Long-term exposure to lower levels
• Higher levels, such as those you might find in an industrial facility, can cause more serious, immediate effects
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Tetrachloroethylene (PCE) • May cause impaired color vision
• Based on a study of dry cleaner workers
• Long term exposure may cause other neurological effects • Changes to mood, memory, and reaction time
• Some limited evidence for certain cancers in humans• Associations with bladder cancer, multiple myeloma, and non-Hodgkin’s
lymphoma
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Trichloroethylene (TCE)• Exposure during a critical period of fetal development may cause
heart defects• Primary population of concern is pregnant women
• May cause changes in immune system function • May cause kidney cancer• Some evidence for an association with liver cancer and non-Hodgkin’s
lymphoma
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Vinyl chloride• Long-term exposure may cause liver cancer
• Angiosarcoma of the liver• Hepatocellular carcinoma
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Personal health evaluation• MDHHS cannot provide medical advice • Talk with your doctor if you have health concerns• Your doctor will be able to provide a personalized evaluation of your
health• Your doctor can talk to a medical toxicologist at Poison Control to get
more information and determine whether specific health tests would be appropriate
• Poison Control – 1-800-222-1222
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